Canister

Abstract

To restrain ventilation resistance while restraining an increase in the number of components.SOLUTION: A canister comprises at least one chamber in which an adsorbent for adsorbing fuel vapor is arranged, an inflow port, an atmosphere port, an outflow port, and a case member. The case member forms a specific chamber that is one of the at least one chamber, and in which a granular adsorbent is arranged. The case member comprises a side wall part, and at least one protruding part. The side wall part spreads from a first end part to a second end part in a flow direction of fluid in the specific chamber, and forms an inner peripheral surface of the specific chamber. The at least one protruding part is formed integrally with the side wall part and protrudes from the inner peripheral surface of the side wall part.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a canister. [Background technology]

[0002] As described in Patent Documents 1 and 2, a technique is known in which a member having multiple rod-shaped parts extending in the same direction is placed in a chamber in a canister in which granular adsorbent is placed. With this technique, gaps are formed between the rod-shaped parts of the member and the granular adsorbent placed in the chamber, thereby reducing the airflow resistance. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2022-164344 A [Patent Document 2] JP 2022-164345 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the canister chamber, the flow of fluid tends to be stagnant near the wall of the case that defines the chamber. In contrast, in the techniques disclosed in Patent Documents 1 and 2, the rod-shaped portion is located mainly in the center of the chamber. Moreover, the rod-shaped portion is formed as a separate member from the case, which may increase the number of parts that make up the canister.

[0005] In one aspect of the present disclosure, it is desirable to suppress airflow resistance while suppressing an increase in the number of parts. [Means for solving the problem]

[0006] One aspect of the present disclosure is a canister configured to be mounted on a vehicle having an engine, the canister comprising at least one chamber, an inflow port, an atmospheric port, an outflow port, and a case member. An adsorbent that adsorbs fuel vapor is disposed in the at least one chamber. The inflow port is configured to allow fuel vapor to flow from a fuel tank of the vehicle into the at least one chamber. The atmospheric port is configured to be open to the atmosphere. The outflow port is configured to allow the fuel vapor adsorbed in the adsorbent to flow out toward the engine by the atmosphere that has flowed in from the atmospheric port. The case member forms a specific chamber, which is one of the at least one chambers and is a chamber in which a granular adsorbent is disposed. The case member also has a side wall portion and at least one protruding portion. The side wall portion extends from a first end to a second end in a flow direction of a fluid in the specific chamber, and forms an inner circumferential surface of the specific chamber. The at least one protruding portion is a portion formed integrally with the side wall portion and protrudes from the inner circumferential surface of the side wall portion.

[0007] According to the above-mentioned configuration, a gap is formed between at least one protrusion formed integrally with the side wall and the granular adsorbent around the inner circumferential surface of the specific chamber, which promotes the flow of fluid around the inner circumferential surface, thereby suppressing the airflow resistance of the canister while suppressing an increase in the number of parts.

[0008] In one aspect of the disclosure, the inlet and outlet ports and / or the atmospheric port may be provided at a first end of the particular chamber, and the at least one protrusion may extend from the first end of the particular chamber along the flow direction.

[0009] According to the above-mentioned configuration, the flow of the fluid around the inner circumferential surface of the specific chamber can be further promoted, and therefore the ventilation resistance of the canister can be suppressed. According to an aspect of the present disclosure, the canister may further include an outer case that is a member forming an outer peripheral surface of the canister and that has at least one chamber provided therein. The case member may be a member disposed inside the outer case.

[0010] According to the above configuration, it is possible to suppress an increase in the number of parts and to reduce the airflow resistance of the canister. In one aspect of the present disclosure, a plurality of protrusions may be arranged on an inner circumferential surface of the side wall portion so as to go around the specific chamber.

[0011] According to the above-mentioned configuration, the flow of fluid around the inner circumferential surface can be further promoted, and thus the airflow resistance of the canister can be further reduced. In one embodiment of the present disclosure, one of the inlet port, the outlet port, and the atmospheric port may be provided at a first end of the specific chamber, and the height of the at least one protrusion from the inner circumferential surface to the top of the protrusion may increase toward the first end.

[0012] In the chamber in which the port is provided, the area where the fluid flow is relatively good is considered to spread out in a roughly fan-like shape in the direction of the fluid flow from the port. In contrast, with the above-described configuration, it is possible to dispose the protrusion in the area where the fluid flow is relatively poor, thereby promoting the fluid flow in that area. This makes it possible to further reduce the airflow resistance of the canister.

[0013] In one aspect of the disclosure, one of the inlet and outlet ports and the atmospheric port may be provided at a first end of the particular chamber. The sidewall may have a constricting portion located around the first end of the particular chamber. The constricting portion may be configured to reduce a cross-sectional area perpendicular to the flow direction in the particular chamber toward the first end. At least one protrusion may be provided at the constricting portion.

[0014] According to the above-mentioned configuration, inside the contraction portion of the specific chamber, the flow of the fluid is promoted by the shape of the contraction portion in addition to the protrusion portion, so that the airflow resistance of the canister can be reduced. [Brief description of the drawings]

[0015] [Figure 1] 2 is a cross-sectional view taken along a fluid flow direction in the canister of the first embodiment. FIG. [Diagram 2]3 is a cross-sectional view of a first chamber in the canister of the first embodiment, taken along a line perpendicular to the fluid flow direction. FIG. [Diagram 3] 4 is a cross-sectional perspective view of a protruding portion of the canister according to the first embodiment; FIG. [Figure 4] 4 is a cross-sectional perspective view of a protruding portion of the canister according to the first embodiment; FIG. [Diagram 5] 4 is a cross-sectional perspective view of a protruding portion of the canister according to the first embodiment; FIG. [Figure 6] FIG. 11 is a cross-sectional view taken along the direction of fluid flow in a canister according to a second embodiment. [Figure 7] 13 is a cross-sectional view taken along the fluid flow direction of a reduced portion of a canister according to a third embodiment. FIG. [Figure 8] 13 is a cross-sectional view taken along the fluid flow direction in a reduced portion of a modified example. FIG. [Figure 9] 13 is a cross-sectional view taken along the fluid flow direction in a reduced portion of a modified example. FIG. [Figure 10] 13 is a cross-sectional view taken along the fluid flow direction in a reduced portion of a modified example. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. Note that the embodiments of the present disclosure are not limited to the following embodiments, and various forms may be adopted as long as they fall within the technical scope of the present disclosure.

[0017] [1. First embodiment] [(1) Canister configuration] A canister 1 of the first embodiment is mounted on a vehicle (see FIG. 1). The canister 1 has a resin outer case 10 that forms an outer peripheral surface, and first and second chambers 20, 30 are provided inside the outer case 10. Adsorbents 4 for adsorbing fuel vapor are disposed in these chambers. The number of chambers in the canister 1 may be, for example, one or three or more.

[0018] An inlet port 11, an outlet port 12, and an atmospheric port 13 are provided at an end of the outer case 10. Hereinafter, the side of the outer case 10 of the canister 1 on which the inlet port 11, the outlet port 12, and the atmospheric port 13 are provided will be referred to as the port side. The outer case 10 also has an opening on the side opposite the port side. The opening is closed by a lid member 14. Hereinafter, the side opposite the port side (in other words, the side on which the lid member 14 is provided) will be referred to as the lid side.

[0019] The first chamber 20 forms a space of a substantially rectangular parallelepiped shape extending from the port side to the lid side, and an inflow port 11 and an outflow port 12 connecting the first chamber 20 to the outside of the canister 1 are provided at the end on the port side (hereinafter, the first end F). The shape of the space in the first chamber 20 is not limited to a substantially rectangular parallelepiped shape, and may be, for example, a cylindrical shape. Filters 21 and 22 are disposed at the first end F and the end on the lid side (hereinafter, the second end S) of the first chamber 20, respectively, and an adsorbent 4 is disposed between the filters 21 and 22. The second end S of the first chamber 20 is connected to the communication passage 15. A permeable porous plate 23 is disposed between the filter 22 on the lid side of the first chamber 20 and the communication passage 15, and a coil spring 16 is disposed between the perforated plate 23 and the lid member 14. The coil spring 16 presses the perforated plate 23 toward the port side.

[0020] The second chamber 30 is adjacent to the first chamber 20, has a smaller volume than the first chamber 20, and has a thin and elongated cylindrical shape extending from the lid side to the port side. The second chamber 30 is not limited to a cylindrical shape, and may be, for example, a rectangular column shape. An atmospheric port 13 that connects the second chamber 30 to the outside of the canister 1 is provided at the port side end (hereinafter, the first end F) of the second chamber 30. As with the first chamber 20, filters 31 and 32 are arranged at the first end F and the lid side end (hereinafter, the second end S) of the second chamber 30, respectively, and an adsorbent 4 is arranged between the filters 31 and 32. The second end S of the second chamber 30 is connected to the communication passage 15, and a porous plate 33 is arranged between the lid side filter 32 and the communication passage 15. Similarly to the first chamber 20, the perforated plate 33 is pressed toward the port side by a coil spring 17 between the perforated plate 33 and the cover member .

[0021] Furthermore, the communication passage 15 is provided along the cover member 14, and connects the first chamber 20 and the second chamber 30. Therefore, inside the canister 1, the fluid can travel between the first chamber 20 and the second chamber 30 via the communication passage 15.

[0022] The inflow port 11 is connected to a fuel tank of the engine of the vehicle. Fuel vapor generated in the fuel tank flows into the inside of the canister 1 through the inflow port 11 and is adsorbed by the adsorbent 4 in each chamber. As a result, fuel is accumulated inside the canister 1.

[0023] The outlet port 12 is connected to an intake pipe of the engine of the vehicle, and the atmospheric port 13 is connected to the outside of the vehicle and is open to the atmosphere. The negative intake pressure of the engine causes the atmosphere (in other words, purge air) to flow into the canister 1 via the atmospheric port 13. The inflow of the purge air causes the fuel vapor adsorbed in the adsorbent 4 to be desorbed, and the desorbed fuel vapor flows out from the outlet port 12 toward the intake pipe together with the purge air. This causes a purge to remove the fuel vapor adsorbed in the adsorbent 4, and the adsorbent 4 is regenerated.

[0024] In the first and second chambers 20, 30, fuel vapor and purge air (hereinafter also referred to as fluid) flow along the direction in which the first end F and the second end S face each other. [(2) Projection] The first and second chambers 20 and 30 are configured as special chambers in which a plurality of protrusions 25 and 35 are provided on the side walls 24 and 34, respectively (see FIG. 1). Note that one of the first and second chambers 20 and 30 may be configured as a special chamber.

[0025] The portion of the outer case 10 that constitutes the first chamber 20 has a side wall 24 (see FIG. 2). The side wall 24 extends from the first end F to the second end S of the first chamber 20, surrounding the first chamber 20 from the side and forming the inner circumferential surface of the first chamber 20. A similar side wall 34 is also provided in the portion of the outer case 10 that constitutes the second chamber 30.

[0026] Each of the side walls 24, 34 is provided with a plurality of protruding portions 25, 35 so as to protrude from the inner peripheral surface. The side walls 24, 34 are made of resin and are integrally formed with the outer case 10. The plurality of protruding portions 25, 35 are also made of resin and are integrally formed with the side walls 24, 34 and, in turn, the outer case 10. In other words, the side walls 24, 34 and the plurality of protruding portions 25, 35 are formed as part of the outer case 10 when the outer case 10 is formed by, for example, injection molding or the like.

[0027] Each of the protrusions 25 of the first chamber 20 is a rib-like elongated portion, and extends linearly from the first end F of the first chamber 20 toward the second end S (in other words, toward the lid side) along the fluid flow direction. However, the present invention is not limited to this, and each of the protrusions 25 may extend toward the lid side while bending or curving, or may extend in a direction different from the fluid flow direction, for example, in a direction perpendicular to the fluid flow direction. In addition, each of the protrusions 25 extends from the first end F to the second end S, as an example. However, each of the protrusions 25 does not have to reach the second end S, and the end of each of the protrusions 25 on the lid side may be located, for example, near the center of the side wall portion 24 in the fluid flow direction or near the first end F. In addition, each of the protrusions 25 may extend from a position away from the first end F. In addition, each of the protrusions 25 may be a rod-shaped portion protruding from the inner circumferential surface of the side wall portion 24.

[0028] Moreover, the multiple protrusions 25 are arranged side by side at approximately regular intervals so as to go around the side surface of the first chamber 20. Of course, this is not limited thereto, and the intervals between adjacent protrusions 25 do not have to be approximately regular. Moreover, the multiple protrusions 25 may be provided at specific locations on the inner circumferential surface of the side wall portion 24, without going around the side surface of the first chamber 20.

[0029] Moreover, the height of each protrusion 25 increases toward the first end F. Here, the height means the length in the protrusion direction of the protrusion 25 between the top of the protrusion 25 and the inner circumferential surface of the side wall portion 24. Of course, this is not limited thereto, and the height of each protrusion 25 may be approximately constant or may increase toward the second end S.

[0030] As an example, each protrusion 25 has a cross section perpendicular to its extension direction (in other words, the flow direction of the fluid) that is substantially polygonal. Specifically, the cross section may be, for example, a triangle, a rectangle, or a pentagon (see FIGS. 2 to 4). In addition, for example, the top of each protrusion 25 may be rounded (see FIG. 5). Furthermore, each protrusion 25 may have the same shape or different shapes.

[0031] The multiple protrusions 35 of the second chamber 30 are configured similarly to the multiple protrusions 25 of the first chamber 20. Also, the first and / or second chambers 20, 30 may be provided with one protrusion 25, 35.

[0032] The adsorbent 4 placed in the specific chamber is composed of pellets, which are granular activated carbon. The pellets may have various shapes, such as a substantially cylindrical or spherical shape. Of course, the adsorbent 4 may be a granular adsorbent made of a material other than activated carbon. On the other hand, the adsorbent 4 placed in the chambers other than the specific chamber is not limited to a granular shape, and various adsorbents may be placed.

[0033] [2. Second embodiment] [(1) Overview] The canister 1 of the second embodiment differs from the first embodiment in the configuration of the second chamber 50 (see FIG. 6). That is, in the canister 1 of the second embodiment, an inner case 5 is disposed inside an outer case 10, and a second chamber 30 is formed inside the inner case 5. Then, only the second chamber 50 is configured as a specific chamber. Of course, the first chamber 20 may also be configured as a specific chamber. The configuration of the second chamber 30 in the canister 1 of the second embodiment will be described below.

[0034] [(2) Storage section] The outer case 10 of the canister 1 is provided with a storage section 18 adjacent to the first chamber 20 (see FIG. 6). The storage section 18 has a long and thin cylindrical shape extending from the lid side to the port side, similar to the second chamber 30 of the first embodiment, and a storage space 19 for storing the inner case 5 is formed inside. The storage section 18 is not limited to a cylindrical shape, and may be, for example, a rectangular column shape. An atmospheric port 13 is provided at an end (hereinafter, first end) of the storage section 18 on the port side. An end (hereinafter, second end) of the storage section 18 is connected to the communication passage 15.

[0035] The inner case 5 is a cylindrical resin member that forms the second chamber 50 therein. The inner case 5 is not limited to a cylindrical shape, and may be, for example, a square tube. A first end of the inner case 5 is adjacent to the atmospheric port 13, and the atmospheric port 13 is provided at an end on the port side of the second chamber 50 (hereinafter, the first end F). A second end of the inner case 5 is adjacent to the communication passage 15, and an end on the lid side of the second chamber 50 (hereinafter, the second end S) communicates with the communication passage 15. The inner case 5 includes a side wall portion 51, filters 52 and 53, a partition plate 54, a grid 55, a contact portion 56, a flange portion 57, and a plurality of protrusions 58 (described in detail below).

[0036] The side wall portion 51 is a cylindrical portion, and the second chamber 50 is formed therein. The side wall portion 51 is not limited to a cylindrical shape, and may be, for example, a square tube shape. Filters 52 and 53 are arranged at the first end F and the second end S of the second chamber 50, respectively, and the granular adsorbent 4 similar to that of the first embodiment is arranged between the filters 52 and 53. The filter 52 at the first end F is supported by a partition plate 54 having permeability from the atmospheric port 13 side. In addition, the second end S of the second chamber 50 is connected to the communication passage 15. A grid 55 through which a fluid can pass is arranged between the filter 53 on the lid side of the second chamber 50 and the communication passage 15, and a coil spring 17 is arranged between the grid 55 and the lid member 14. The coil spring 17 presses the grid 55 toward the port side.

[0037] Further, the abutment portion 56 is provided so as to surround the opening located at the first end portion of the inner case 5. The abutment portion 56 abuts against the storage portion 18 at a step portion provided in the vicinity of the first end portion of the storage portion 18, and is supported by the step portion.

[0038] Flange portion 57 is a flange-shaped portion that is provided so as to surround an opening located at the second end of inner case 5 and protrudes laterally. An end face of flange portion 57 abuts against storage portion 18 at the second end of storage portion 18. A groove is formed in the end face of flange portion 57 so as to surround the opening of inner case 5, and a seal member (an O-ring, as an example) is disposed in the groove. The seal member abuts against storage portion 18.

[0039] [(3) Projection] The second chamber 50 is configured as a specific chamber in which a plurality of protruding parts 58 are provided protruding from the inner peripheral surface of the side wall part 51 of the inner case 5 (see FIG. 6). The plurality of protruding parts 58 are configured similarly to the plurality of protruding parts 25, 35 in the first embodiment.

[0040] That is, the multiple protrusions 58 are made of resin and are formed integrally with the side wall portion 51, and ultimately with the inner case 5. Similarly to the first embodiment, the multiple protrusions 58 are elongated rib-like portions and extend from the first end F of the second chamber 50 toward the second end S along the fluid flow direction. As an example, each protrusion 58 extends from the first end F to the second end S of the second chamber 50, but each protrusion 58 may be spaced apart from the first end F and / or the second end S.

[0041] Moreover, similarly to the first embodiment, the multiple protrusions 58 are arranged side by side at substantially regular intervals so as to go around the side surface of the second chamber 50, and the height of each protrusion 58 decreases toward the second end S. However, this is not limited thereto, and the arrangement and height of the multiple protrusions 58 can be determined appropriately. Furthermore, the cross-sectional shape of each protrusion 58 is also determined similarly to the first embodiment.

[0042] [3. Third embodiment] [(1) Overview] The canister 1 of the third embodiment differs from the first embodiment in that two reduced sections 27 are provided in the first chamber 20, which is a specific chamber (see FIG. 7). The reduced sections 27 are provided around a first end F of the first chamber 20 (in other words, the specific chamber), and are configured so that the area of ​​a cross section perpendicular to the fluid flow direction in the first chamber 20 is reduced toward the port side (in other words, the first end F).

[0043] In the third embodiment, the side wall portion 24 includes a main body portion 26 and two reduced portions 27. The main body portion 26 is a portion that includes the lid-side end portion of the side wall portion 24. The two reduced portions 27 are provided at the port-side end portion of the main body portion 26, aligned in a direction perpendicular to the fluid flow direction, more specifically, along the direction in which the first chamber 20 and the second chamber 30 are aligned.

[0044] Moreover, the first end F of the first chamber 20 is formed by the port side ends of the two reduction sections 27. These ends (in other words, each first end F) are provided with an inflow port 11 and an outflow port 12. Moreover, each first end F of the first chamber 20 is provided with a filter 21.

[0045] The two reduced portions 27 are formed integrally with the side wall portion 24, and ultimately with the outer case 10. Each reduced portion 27 is provided with a plurality of protruding portions 25. Details of the reduced portion 27 and the configuration of the plurality of protruding portions 25 will be described below.

[0046] [(2) Details of the reduced area] The reduced section 27 corresponding to the inflow port 11 is provided so as to extend from the first end F where the inflow port 11 of the first chamber 20 is provided, toward the lid side (in other words, toward the second end S) (see FIG. 7). On the other hand, the reduced section 27 corresponding to the outflow port 12 is provided so as to extend from the first end F where the outflow port 12 of the first chamber 20 is provided, toward the lid side.

[0047] Each of the reduced portions 27 surrounds the area around the corresponding port in the first chamber 20. Each of the reduced portions 27 is tapered. That is, each of the reduced portions 27 extends linearly in a cross section that passes through the inlet port 11 or the outlet port 12 and includes an imaginary axis A that extends in the fluid flow direction. Each of the reduced portions 27 is inclined with respect to the fluid flow direction so as to approach the axis A toward the port side.

[0048] [(3) Projection] A plurality of protrusions 25 protruding from the inner circumferential surface of each reduced portion 27 are provided on the inner circumferential surface (see FIG. 7). The plurality of protrusions 25 are made of resin and are integrally formed with the reduced portion 27 in which the plurality of protrusions 25 are provided, and further with the side wall portion 24 and the outer case 10. The plurality of protrusions 25 may be provided on one of the two reduced portions 27.

[0049] Each protrusion 25 is a rib-like elongated portion similar to the first embodiment, and extends from the port side end (in other words, the first end F) of each reduction section 27 to the lid side end along the fluid flow direction. However, this is not limited thereto, and each protrusion 25 may reach the main body section 26 beyond the lid side end of the reduction section 27, or may not reach that end. Furthermore, each protrusion 25 may be spaced apart from the first end F of the reduction section 27. Furthermore, the multiple protrusions 25 are arranged side by side at approximately regular intervals so as to go around the side surface of each reduction section 27, similar to the first embodiment.

[0050] Here, the region extending from the end face forming the outlet port 12 or the first end F corresponding to the outlet port 12 in the first chamber 20 toward the lid side along the fluid flow direction is referred to as the front region 20A. The front region 20A is a columnar region whose cross section perpendicular to the extension direction has the same shape as the end face. The top of each protrusion 25 extends along the boundary of the front region 20A. Of course, the shape of the end of each protrusion 25 is not limited to this, and can be determined as appropriate.

[0051] [(4) Variation 1] The reduced portion 27 may be provided around the first end F of the first chamber 20 at a position slightly away from the first end F (see FIG. 8). Specifically, the side wall portion 24 of the first chamber 20 may be provided with the reduced portion 27 and a straight portion 28 corresponding to the inflow port 11 or the outflow port 12.

[0052] The straight portion 28 is a cylindrical portion that extends substantially straight along the fluid flow direction. That is, the straight portion 28 has a substantially constant cross section perpendicular to the fluid flow direction. The cross section has substantially the same shape as the end face that forms the first end F of the first chamber 20.

[0053] The straight portion 28 is provided so as to extend from a first end F where a corresponding port in the first chamber 20 is provided, toward the lid side, and the reduced portion 27 is provided at the end of the straight portion 28 on the lid side. The end of the reduced portion 27 on the lid side is connected to the main body portion 26. In other words, the straight portion 28 and the reduced portion 27 surround the area around the corresponding port in the first chamber 20.

[0054] For example, the contraction portion 27 has a tapered shape. Also, for example, both ends of the contraction portion 27 in the fluid flow direction may be rounded. As in the third embodiment, a plurality of protrusions 25 are provided on the inner circumferential surface of the reduced portion 27. As in the third embodiment, each protrusion 25 extends in the fluid flow direction from the port side end to the lid side end of each reduced portion 27, and its apex extends along the boundary of the front region 20A. Of course, this is not limiting, and the shape and arrangement position of each protrusion 25 can be determined appropriately.

[0055] In addition, the shape of the reduced portion 27 is not limited to a tapered shape and can be determined appropriately. Specifically, for example, the reduced portion 27 may be a stepped portion that expands in a direction substantially perpendicular to the fluid flow direction (see FIG. 9).

[0056] The number of the reduction portions 27 and the straight portions 28 provided corresponding to the inflow port 11 or the outflow port 12 may be appropriately determined. As an example, as shown in FIG. 9, first and second stepped reduction portions 27A, 27B and first to third straight portions 28A to 28C may be provided corresponding to the inflow port 11 or the outflow port 12. That is, the first straight portion 28A is provided so as to extend toward the lid from the first end portion F where the corresponding port in the first chamber 20 is provided, and the first reduction portion 27A is provided at the end portion on the lid side of the first straight portion 28A. Furthermore, the second straight portion 28B is provided so as to extend toward the lid from the end portion on the outer periphery side of the first reduction portion 27A, and the second reduction portion 27B is provided at the end portion on the lid side of the second straight portion 28B. Furthermore, a third straight portion 28C is provided so as to extend from the outer circumferential end of the second reduced portion 27B towards the lid side, and the lid side end of the third straight portion 28C is connected to the main body portion 26. In other words, the first to third straight portions 28A to 28C and the first and second reduced portions 27A, 27B surround the areas around the corresponding ports in the first chamber 20.

[0057] Similarly to the third embodiment, a plurality of protrusions 25 are provided on the inner circumferential surfaces of the second and third straight portions 28B, 28C and the first and second reduced portions 27A, 27B. Each protrusion 25 extends in the fluid flow direction from the port side end to the lid side end of each of these portions, and its apex extends along the boundary of the front region 20A. Of course, the shape and arrangement of each protrusion 25 are not limited to this and can be determined appropriately.

[0058] The reduced portion 27 and straight portion 28 may be provided corresponding to either the inflow port 11 or the outflow port 12, or may be provided corresponding to each of these ports. Similarly, a reduced portion and a plurality of protrusions may be provided on the side wall 34 of the second chamber 30 corresponding to the atmospheric port 13 in the second chamber 30. Similarly, a reduced portion and a plurality of protrusions may be provided on the side wall 51 of the second chamber 50 formed by the inner case 5 of the second embodiment corresponding to the atmospheric port 13.

[0059] [(5) Variation 2] The reduced portion 27 may be provided corresponding to the inflow port 11 and the outflow port 12 (see FIG. 10). That is, the reduced portion 27 may be provided so as to extend from a single first end F, where the inflow port 11 and the outflow port 12 are provided in the first chamber 20, toward the second end S. In other words, the reduced portion 27 surrounds the area around the inflow port 11 and the outflow port 12 in the first chamber 20.

[0060] The reduction section 27 may be tapered, for example. As in the third embodiment, a plurality of protrusions 25 are provided on the inner circumferential surface of the reduction section 27. Each protrusion 25 extends from the port side end of the reduction section 27 to the lid side end along the fluid flow direction, and its apex extends along the boundary of the front area 20A. Note that the front area 20A in the second modification refers to an area extending from the end face forming the first end F where the outlet port 12 and the outlet port 12 are provided in the first chamber 20 to the lid side along the fluid flow direction. Of course, the shape and arrangement of each protrusion 25 are not limited to this, and may be determined as appropriate.

[0061] In addition, in the second modification, similarly to the first modification, linear portions 28 may be provided together with the reduced portions 27, and the number of the reduced portions 27 and the linear portions 28 may be determined appropriately. The shape of the reduced portions 27 is not limited to a tapered shape, and may be, for example, a stepped shape. Also, in such a case, similarly to the third embodiment or the first modification, a plurality of protrusions 25 may be provided on the inner peripheral surface of the reduced portions 27.

[0062] [4. Effects] (1) According to the above embodiment, a gap is formed between each protrusion and the granular adsorbent around the inner circumferential surface of the side wall of the specific chamber, and therefore the flow of fluid around the inner circumferential surface can be promoted. In addition, each protrusion is integrally formed with the outer case 10 or the inner case 5. Therefore, the air flow resistance of the canister 1 can be suppressed while suppressing an increase in the number of parts, and as a result, the desorption performance of the fuel vapor adsorbed by the adsorbent is improved. Furthermore, the improved desorption performance makes it possible to efficiently accumulate the fuel vapor with a small amount of the adsorbent 4, and therefore the adsorption performance of the fuel vapor is improved. In addition, by configuring the first chamber 20, which has a relatively large volume, as the specific chamber, the desorption performance and adsorption performance can be improved more effectively.

[0063] (2) Furthermore, each of the protrusions 25, 35, 58 extends from the first end F of the specific chamber along the direction of fluid flow. This further promotes the flow of fluid around the inner circumferential surface of the specific chamber, thereby reducing the airflow resistance of the canister 1.

[0064] (3) Furthermore, in the third embodiment, inside the contraction portion 27 in the specific chamber, the flow of fluid is promoted by the shape of the contraction portion 27 in addition to the multiple protrusions. Therefore, the airflow resistance of the canister 1 can be suppressed.

[0065] (4) Furthermore, the protrusions 25, 35, 58 are arranged side by side around the side surfaces of the side walls 24, 34, 51. This further promotes the flow of fluid around the inner circumferential surfaces of the side walls 24, 34, 51. This further reduces the airflow resistance of the canister 1.

[0066] (5) In addition, in a chamber in which a port is provided, the region where the fluid flow is relatively good is considered to spread out in a roughly fan-like shape from the port along the fluid flow direction in a cross section including the axis A. In contrast, according to the above embodiment, the height of each of the protrusions 25, 35, 58 increases toward the first end F of the specific chamber, so that the protrusions can be disposed in the region where the fluid flow is relatively poor. This makes it possible to promote the fluid flow in that region, and as a result, the airflow resistance of the canister can be further suppressed.

[0067] 5. Other embodiments (1) The number of chambers provided in the canister 1 is not limited to two as in the above embodiment, and may be determined as appropriate. The chamber configured as the specific chamber may also be determined as appropriate. The canister 1 may have a chamber in which no port is provided, and such a chamber may be configured as the specific chamber. For example, the first chamber may be configured by an inner case, and such a first chamber may be configured as the specific chamber, without being limited to the second chamber.

[0068] (2) In the above embodiment, the canister 1 may be formed by assembling a plurality of case members. In other words, the outer peripheral surface of the canister 1 may be formed by a plurality of case members, and at least one chamber may be provided inside each of the case members. In such a case, a plurality of protrusions in a specific chamber may be formed integrally with the case member that constitutes the specific chamber.

[0069] (3) Multiple functions possessed by one component in the above embodiments may be realized by multiple components, or one function possessed by one component may be realized by multiple components. Also, multiple functions possessed by multiple components may be realized by one component, or one function realized by multiple components may be realized by one component. Also, part of the configuration of the above embodiments may be omitted. Also, at least part of the configuration of the above embodiments may be added to or substituted for the configuration of another of the above embodiments.

[0070] [6. Technical Concepts Disclosed in This Specification] [Item 1] A canister configured to be mounted on a vehicle having an engine, at least one chamber having an adsorbent disposed therein for adsorbing fuel vapor; an inlet port configured to admit fuel vapor from a fuel tank of the vehicle into the at least one chamber; an atmospheric port configured to be open to the atmosphere; an outlet port configured to allow the fuel vapor adsorbed in the adsorbent to flow out toward the engine by the atmospheric air flowing in from the atmospheric air port; a case member that forms a specific chamber, which is one of the at least one chambers, in which a granular adsorbent is placed; The case member is a sidewall portion that extends from a first end to a second end in a fluid flow direction in the specific chamber and forms an inner circumferential surface of the specific chamber; At least one protrusion that is integrally formed with the side wall and protrudes from the inner circumferential surface of the side wall. Canister.

[0071] [Item 2] Item 1. A canister according to item 1, one of the inlet port, the outlet port, and the atmospheric port is provided at the first end of the specific chamber; The at least one protrusion extends from the first end of the particular chamber along the flow direction. Canister.

[0072] [Item 3] The canister according to item 1 or 2, The canister further includes an outer case that is a member that forms an outer peripheral surface of the canister and in which the at least one chamber is provided, The case member is a member disposed inside the outer case. Canister.

[0073] [Item 4] A canister according to any one of items 1 to 3, A plurality of the protrusions are arranged on the inner peripheral surface of the side wall portion so as to go around the specific chamber. Canister.

[0074] [Item 5] A canister according to any one of items 1 to 4, one of the inlet port, the outlet port, and the atmospheric port is provided at the first end of the specific chamber; The at least one protrusion has a height from the inner circumferential surface to a top of the protrusion increasing toward the first end. Canister.

[0075] [Item 6] A canister according to any one of items 1 to 5, one of the inlet port, the outlet port, and the atmospheric port is provided at the first end of the specific chamber; the sidewall portion has a reduced portion located around the first end of the particular chamber; The reduction section is configured to reduce an area of ​​a cross section perpendicular to the flow direction in the specific chamber toward the first end, The at least one protrusion is provided on the reduced portion. Canister.

[0076] [7. Correspondence of Words] The outer case 10 in the first and third embodiments and the inner case 5 in the second embodiment correspond to an example of a case member. [Explanation of symbols]

[0077] 1...canister, 10...outer case, 11...inlet port, 12...outlet port, 13...atmospheric port, 18...storage section, 19...storage space, 20...first chamber, 24...side wall portion, 25...protruding portion, 27, 27A, 27B...reduced portion, 28, 28A, 28B, 28C...straight portion, 30...second chamber, 34...side wall portion, 35...protruding portion, 4...adsorbent, 5...inner case, 50...second chamber, 51...side wall portion, 58...protruding portion.

Claims

1. A canister configured to be mounted on a vehicle having an engine, at least one chamber having an adsorbent disposed therein for adsorbing fuel vapor; an inlet port configured to admit fuel vapor from a fuel tank of the vehicle into the at least one chamber; an atmospheric port configured to be open to the atmosphere; an outlet port configured to allow the fuel vapor adsorbed in the adsorbent to flow out toward the engine by the atmospheric air flowing in from the atmospheric air port; a case member that forms a specific chamber, which is one of the at least one chambers, in which a granular adsorbent is placed; The case member is a sidewall portion that extends from a first end to a second end in a fluid flow direction in the specific chamber and forms an inner circumferential surface of the specific chamber; At least one protruding portion that is integrally formed with the side wall portion and protrudes from the inner circumferential surface of the side wall portion. Canister.

2. 2. The canister of claim 1, one of the inlet port, the outlet port, and the atmospheric port is provided at the first end of the specific chamber; The at least one protrusion extends from the first end of the particular chamber along the flow direction. Canister.

3. 3. The canister according to claim 1 or 2, an outer case that forms an outer peripheral surface of the canister and in which the at least one chamber is provided; The case member is a member disposed inside the outer case. Canister.

4. 3. The canister according to claim 1 or 2, A plurality of the protrusions are arranged on the inner peripheral surface of the side wall portion so as to go around the specific chamber. Canister.

5. 3. The canister according to claim 1 or 2, one of the inlet port, the outlet port, and the atmospheric port is provided at the first end of the specific chamber; The at least one protrusion has a height from the inner circumferential surface to a top of the protrusion increasing toward the first end. Canister.

6. 3. The canister according to claim 1 or 2, one of the inlet port, the outlet port, and the atmospheric port is provided at the first end of the specific chamber; the sidewall portion has a reduced portion located around the first end of the particular chamber; The reduction section is configured to reduce an area of ​​a cross section perpendicular to the flow direction in the specific chamber toward the first end, The at least one protrusion is provided on the reduced portion. Canister.

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